Flat knitting machine with automatic transfer device

ABSTRACT

A knitted border is guided from the needles of a flat knitting machine to the points of a transfer bar releasably secured on the machine below the needle beds by gravity along guide wires passing through stitches in the last-knitted course. The stitches are transferred from the needles to the wires by the action of a cam on the knitting carriage.

0 United States Patent [151 3,677,037

Krause [4 1 July 18, 1972 s41 FLAT KNITTING MACHINE WITH 3,222,313 101132; 130m "225148 TIC T FE D VICE 5 1 ontame 148 AUTO S R E 3,514,978 6/1970 Bliederhauser. ....66/148 [72] inventor: Erich Krause, Bopfingen, Germany 3,563,063 2/1971 Blood et a1 ..66/ 148 [73] Assignee: Universal Maschlnenfabrik Dr. Rudolf Schieber KG, Westhausen, Germany Primary Examiner-Ronald Feldbaum 221 Filed: Jan. 19, 1971 36mm" [21] Appl. No.: 107,678 [57] ABSTRACT 8" Application Data A knitted border is guided from the needles of a flat knitting machine to the points of a transfer bar releasably secured on Jan. 30, 1970 Germany ..P 20 04 286.8 the machine below the needle beds y g y along guide wires passing through stitches in the last-knitted course. The US. Cl ..66/147 stitches are uansfened from the needles to the wires y the 5s 1 Field of Search ..66/1-47, 148, 149, 150 kmtmg mmage' [56] References Cited 7 Claims, 17 Drawing Figures UNITED STATES PATENTS 3,304,749 2/1967 Stouhase ..66/147 PATENTED JUL] 8 I972 sum 03 0F 10 Fig. 5

INVENTOR BYI PATENTEDJUH a 1912 3,577,037

sum 05 0F 10 INYEXTURi [fr/a9 Krquse;

BYI V44... m MM PATENTED Jun 8 I972 SHEET 07 HF 10 INVEXTUR' E/w'cf K 40 sc, BYI m M MM PATENTEUJULWIQTZ sum 09 or 10 INVEXTUR' Flak? Kka use; 3Y3 MM Md Ma FLAT KNITTING MACHINE WITII AUTOMATIC TRANSFER DEVICE This invention relates to a flat knitting machine, and particularly to an automatic device for transferring a knitted fabric from the knitting needles of the machine to points on a transfer bar.

It is not normally possible to produce borders for knitted garments and the like on the same machine on which the main portions of the garment are knitted. The borders are normally required to be stronger and more resilient than the remainder of the fabric. It has been common practice heretofore manually to shift the stitches of the last-knitted course in a knitted border to the points of a transfer bar, and thereafter to connect the main portion of the fabric to the border or to knit the main portion to the last course of the border.

It is generally desirable that the border have more stitches in each course than a corresponding width of the other fabric, and it is therefore usual to double stitches, for example, every fifth stitch, in the penultimate course of the border, and to knit a last course having single stitches only on those needles which still carry stitches. The stitches of the last course are then applied by hand to sequential points of the transfer bar.

The labor involved requires great skill, and the manual operation is time consuming and expensive. Automatic transfer devices have therefore been proposed heretofore. However, the known automatic devices are complex and costly and operate relatively slowly. None of the known automatic devices in present practical use permits the border and the main portion of a fabric to be knitted on machines of different needle gage. The transfer bars are located above the needle beds while receiving the knitted borders and thereby interfere with normal knitting operation.

It is a primary object of this invention to provide an automatic device for transferring knitted material from the needles of a flat knitting machine to points of a transfer bar which is simpler in its structure and operation than the devices known heretofore, and which operates at greater speed. Another object is the provision of a transfer device capable of duplicating the quality of manually transferred goods.

In one of its more specific aspects, the invention provides an otherwise conventional flat knitting machine having two straight needle beds with mounting means for releasably mounting an elongated transfer member on the frame of the machine in a position in which it is elongated in the common direction of needle bed elongation and downwardly spaced from the needle beds. A guide arrangement guides the stitches of a fabric knitted on one of the needle beds to the set of points on the transfer member. The guide arrangement includes a set of elongated guide members dimensioned to be received in the stitches of the fabric. An upper terminal portion of each guide member is located adjacent a respective knitting needle and a lower terminal portion adjacent a respective point on the transfer member. The guide members are spaced from each other to permit stitches to slide simultaneously from the upper to the lower terminal portions of the several guide members. The stitches are transferred from the knitting needles to the adjacent upper terminal portions of the guide members in response to the normal reciprocating carriage movement.

The spacing of the upper terminal portions of the guide members may be chosen different from the spacing of the lower terminal portions, thereby making it possible to transfer the fabric from a needle bed to a transfer bar when the spacing of the knitting needles on the needle bed is different from the spacing of the points on the transfer bar.

In order to facilitate the shifting of the stitches from the knitting needles on one needle bed to the upper terminal portions of the guide members, the other needle bed is automatically moved away in timed sequence with the carriage movement.

For smooth passage of the stitches from the guide members to the points on the transfer bar, the lower portions of the guide members, the points, or both are formed with recesses, and the members are moved relative to each other in timed sequence with the carriage movement toward and away from a position in which one member is received in the recess of a corresponding other member, and the members of the pair are aligned in the direction of elongation of the guide member.

The upper terminal portions of the guide members are preferably hook-shaped at their free ends and directed to the cooperating needle bed, and a part of each guide member spacedly adjacent the free end is offset laterally for abutting engagement with the needle bed when the lower terminal portion of the guide member is moved upwardly away from the associated point on the transfer bar.

The mechanism which transfers the stitches from the knitting needles to the upper terminal portions of the guide members includes a resilient member mounted on the upper portion of each guide member and a cam on the carriage which engages the resilient members and thereby moves the upper portions of the guide members toward the knitting needles in timed sequence with the carriage movement.

Other features, additional objects, and many of the attendant advantages of this invention will readily be appreciated as the same becomes better understood by reference to the following detailed description of a preferred embodiment when considered in connection with the appended drawing in which:

FIG. I shows a flat knitting machine equipped with the transfer device of the invention in rear elevation;

FIG. 2 shows the machine of FIG. 1 in enlarged fragmentary section on the line IIII;

FIG. 3 illustrates the machine of FIG. 1 in side elevational section on the line IIIIII;

FIG. 4 shows a detail of the apparatus of FIG. 3 on a larger scale;

FIG. 5 shows elements of the machine of FIG. 1 about the knitting space in side elevational section on a larger scale;

FIGS. 6 and 7 show the device of FIG. 5 in other operating positions;

FIG. 8 illustrates a portion of the device of FIG. 7 in plan view;

FIG. 9 shows a portion of the carriage of the knitting machine and associated elements in side elevation;

FIG. 10 illustrates elements of the knitting machine in a plan view;

FIG. 11 illustrates the device of FIGS. 5 to 7 in yet another operating position;

FIG. 12 shows a modified transfer device and associated elements of the knitting machine in a fragmentary view corresponding to that of FIG. 1;

FIG. 13 is an enlarged view of a detail common to the devices of FIGS. I and 12;

FIG. 14 illustrates an automatic needle bed moving device of the machine of FIG. 1 in a view similar to those of FIGS. 5 to 7;

FIG. 15 shows the device of FIG. 14 in fragmentary front elevation;

FIG. 16 shows a portion of the device of FIG. 12 on a greatly enlarged scale; and

FIG. 17 illustrates the device of FIG. 16 in fragmentary top plane view.

Referring now to the individual Figures of the drawing, and initially to FIG. 1, there is seen a flat knitting machine, conventional as far as not described in detail, whose frame 37, 38 carries two flat needle beds, normally arranged in an inverted V-shape, only the rear bed 5 being visible in FIG. 1. A carriage 14 is moved back and forth along the needle beds. It carries knitting cams in a cam box 31 and may take yarn guides 32 along under the control of a pattern mechanism of which only Jacquard cards 33 are seen in the drawing. The knitted fabric is drawn off by means of a bar 2 set with hooks 4 which engage the stitches in the first knitted course. Weights 7 attached to the bar 2 determine the drawoff force exerted on the knitted material. The apparatus described so far is conventional, and its operation is too well understood to require explanation.

This invention is more specifically concerned with a transfer mechanism which automatically transfers a knitted border from the knitting needles of the needle beds to a transfer bar 24 whose two ends are releasably inserted in brackets 26 adjustably fixed on the frame 37,38 below the needle beds, A multiplicity of upright, parallel guide wires 18 leads from the needle beds to the transfer bar, the bar being set with points not visible in FIG. 1. The wires are mounted on a carrier 13 which may be moved vertically on the frame 37,38. The manner in which the wires 18 are attached to the carrier 13 will be described hereinbelow with reference to FIGS. l2, l6, and 17.

As is seen in FIG. 2, the two longitudinal ends of the carrier 13 are each provided with two vertically offset ball bearings 28 of which only one is seen in the drawings. The ball bearings are guided in confining channel 39 attached to the knitting machine frame.

As is better seen in FIG. 3, the two needle beds 5, 6 are each equipped with latch needles 1 which cooperate during knitting of borders 8 in a conventional manner when the carriage 14 travels along the beds. In addition to the knitting cams in the cam box 31, not illustrated in detail, a cam 15 is mounted on the carriage 14 above the rear needle bed 5. Its purpose will presently become apparent.

A radial cam 10 rotatably mounted on the machine frame 37,38 engages a rocker 11 connected to the carrier 13 by links 12 for raising and lowering the same when the cam 10 is turned. The draw-off bar 2 may be raised by means of a supporting bar 35, better seen in FIGS. to 7, whose ends are attached to chains 3 of which only one is seen in FIG. 2. Each chain 3 is trained in a continuous loop over three sprockets 3 of which one is driven by a reversible electric motor 36 controlled by the pattern mechanism 33, the cam being linked with the machine drive through transmissions, conventional in themselves and controlled by the pattern mechanism of the machine in the manner described below with reference to FIG. 14 so as to raise and lower the carrier 13 and the draw-off bar 2 in synchronization with the carriage movements.

The machine is shown in FIG. 3 prior to the beginning ofa knitting cycle. As is better seen in FIG. 4, three completed knitted borders are suspended from the points 25 of the transfer bar 24, the first course of the last-knitted border 8 still being engaged by the hooks 4 on the draw-off bar 2.

As is shown in FIG. 5, the draw-off bar 2 is raised by the chains 3 at the beginning of the knitting cycle until the hooks 4 project into the knitting space between the needle beds 5, 6, and the first course of stitches is knitted on the hooks, as is known in itself. Knitting of the border thereafter continues while the draw-off bar 2 is being lowered.

The last course of stitches is formed on the needles of the from bed 6, and the rear bed 5 is lowered, as will be described below with reference to FIGS. 14 and 15, to provide a gap 9 between the beds wide enough to permit the guide wires 18 to be raised toward the knitting needles 1 of the needle bed 6, as shown in FIGS. 6 and 7.

The pointed top ends 17 of the wires 18 are backed by respective leaf springs 16, best seen in FIG. 8, the top ends of the wire 18 and spring 16 being bent in opposite directions, and the top end 17 as a whole being angularly offset from the main portion of each wire 18.

When the last course of the border 8 is knitted (FIG. 7), the stitches of the last course are retained between the needle shanks and respective, resilient spreader blades 19 associated with each needle which hold the loops of the stitches open. The hook-shaped top ends 17 of the wires 18 are raised to the level of the stitches by the carrier 13, and the cam 15 on the carriage 14 deflects the springs 16 and the wire ends 17 toward the needles 1 during a subsequent traverse of the carriage 14 until the hook ends of the wires enter the loops of respective stitches.

The needles 1 are then lowered by the non-illustrated knitting cams on the carriage 14 into the position seen in FIG. 11, and the stitches 21 in the last course are thereby transferred to the top ends 17 of the wires 18 where they are held momentarily by the springs 16 until the latter are released by the cam 15, and the springs in turn release the stitches for downward sliding movement along the wires 18 when the carrier 13 is lowered toward the transfer bar 24. Premature release of the stitches from the top end 17 is prevented by abutting engagement of the bends in the wires 18 with the needle bed 6, thereby keeping the top end 17 in a slot of the as- O sociated spring 16, as is shown in FIG. 11, whereby the top end 17 and the spring 16 jointly form a downwardly closed V- shaped receptacle for the stitch 21.

The sequential cooperation of the cam 15 with the several springs 16 and top ends 17 of the wires 18 is best seen in FIG. 10 which also shows the needles 1 and the spreader blades 19 associated therewith. As is shown in FIG. 9, the cam 15 is mounted on the carriage 14 by means of a toothed segment 48 rotatable on a shaft 46. The segment 48 meshes with a rack 47 slidable on the carriage and shifted during carriage movement by non-illustrated cams on the machine frame which are swung into and out of respective operative positions under control of the pattern mechanism 33, as is conventional in itself. The cam 15 is moved toward and away from the position shown in FIG. 7 by the shifting rack 47.

While parallel wires 18 have been shown on the carrier 13 in FIG. 1, it is often necessary that the wires converge in a direction from the needles 1 to the transfer bar 24, as is shown in FIG. 12 or in the opposite direction. Even when the gage of the needles 1 is the same as that of the points 25 on the bar 24, not all needles carry stitches in the last-knitted course of the border 8 that is to be transferred. It is normally desirable that most courses in the border have more stitches than the other fabric to which the border is to be joined in a looper. Yet, the number of stitches in t2 last course must be equal to that in the adjoining part of the other fabric. Some doubling of stitches during knitting of the border is necessary and results in needles 22 being empty at the time of transfer.

The wires 18 are readily arranged in a downwardly converging pattern for guiding the unevenly spaced stitches of the last border course from the knitting needles 1 to uniformly, but more narrowly spaced points 25 on the transfer bar, the lowermost portions 23 of the wires being correspondingly spaced, as is shown in FIG. 12.

As is shown in FIG. 13, the free ends of the points 25 and of the lowermost wire portions 23 are provided with recesses 27 which permit the wire ends to be coupled closely to the points by engagement of the wire portion 23 in the recesses of the points 24 and vice versa while the stitches slide downwardly over the joint so formed,

A converging pattern of guide wires 18 is advantageous when the cut of the needles on the knitting machine used for knitting the borders 8 is coarser than that of the needles on which the other fabric was knitted, and a downwardly diverging group of wires 18 may be useful in the opposite relationship of fabric gages.

The mechanism for raising and lowering the rear needle bed 5 is shown in FIGS. 14 and 15 to the extent necessary for its understanding, supporting structure and other conventional elements having been omitted. An eccentric cam 40 is connected to the main drive of the knitting machine in a non-illustrated manner so as to make two revolutions during each reciprocating movement of the carriage 14. A cam follower arm 41 is pivoted by the cam 40 on a fixed shaft 43 which also provides a fulcrum for a lever 42. One arm of the lever 42 is hingedly attached to the needle bed 5, whereas the other arm may be coupled to the cam follower 41 by the pin-shaped armature 44 of an electromagnet 45 which engages an opening in the lever 42 when the magnet 45 is energized by a non-illustrated switch operated by the pattern mechanism 33. It will be appreciated that the mechanism shown in FIGS. 14 and 15 is duplicated along the needle bed 5 as often as may be needed for lifting and lowering the long needle bed. The several cams 40 are mounted on a common shaft, and the several magnets 45 arranged in circuit with a common switch.

The manner in which the wires 18 are secured to the carrier 13, yet permit the stitches 21 of the borders 8 to slide to the lowermost wire portions 23 and to the points 25 will now be described with reference to FIGS. 12, I6, and 17, and it will be understood that the straight wires 18 shown in FIG. 1 are secured to the carrier 13 in the same manner.

Two pairs of horizontal bars 58 fixedly mounted on the carrier l3 closely adjacent the upper and lower ends of the wires 18 respectively carry fixed jaws 49. Another bar 51 slidably mounted between the fixed bars 58 of each pair carries jaws 50. The wires 18, or at least those portions of the wires which are within range of the jaws 49, 50, are of rounded triangular cross section best seen in FIG. 17. A helical tension spring 57 attached to the carrier 13 normally holds the bar 51 in a position in which upper and lower portions of each wire 18 are clamped between two fixed jaws 49 and a movable jaw 50 (FIG. 16). Two electromagnets 52 are attached to the bars 51 respectively and open the clamps formed by the jaws 49, 50 against the restraint of the springs 57 when energized.

Four photoelectric cells 53, 54, 55, 56 are arranged along the downward path of the draw-off bar 2 and are illuminated by respective light sources, not shown, unless the descending bar intercepts the light beam. The photoelectric cells are arranged in the energizing circuits of the magnets 52 in a manner to energize the upper electromagnet 52 when the bar 2 cuts off light to the cell 53, and to deenergize the upper magnet 52 when the bar 2 passes the next photoelectric cell 54. The upper jaws 49, 50 are thereby opened to permit free movement of the descending border 8 while the wires 18 are held in position by the lower jaws 49, 50. As the draw-off bar passes the cells 55, 56, the jaws at the lower ends of the wires 18 are opened long enough to permit the stitches of the lastknitted course of the border 8 to be transferred to the points 25. the correct position of the lowermost wire portions 23 being maintained by conforming engagement with the points 25. The photoelectric cell circuit is deactivated during the upward movement of the bar 2.

It should be understood, of course, that the foregoing disclosurerelates only to a preferred embodiment of the invention, and that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purpose of the disclosure which do not constitute departures from the spirit and scope of the invention set forth in the appended claims.

What is claimed is:

I. In a knitting machine having a frame, two straight needle beds mounted on said frame, said needle beds being elongated in a common, horizontally extending direction and transversely spaced so as to define a knitting space therebetween, a set of knitting needles juxtaposed in said common direction in substantially uniformly spaced relationship, each knitting needle being movable on the associated needle bed into and out of said knitting space, and operating means for moving said needles in times sequence, said operating means including a carriage mounted on said frame for reciprocating movement in said common direction, the improvement which comprises:

a. an elongated transfer member carrying a set of point members in longitudinally and substantially uniformly spaced relationship;

b. mounting means for releasably mounting said transfer member on said frame in a position in which said transfer member is elongated in said common direction and downwardly spaced from said needle beds;

c. guide means for guiding respective stitches of a fabric knitted on one of said needle beds to said transfer member,

I. said guide means including a set of elongated guide members dimensioned to be received in said stitches,

2. each guide member having an upper terminal portion adjacent a respective knitting needle on said one needle bed and a lower terminal portion adjacent a respective point member on said transfer member,

3. said guide members being spaced from each other in said common direction; and d. stitch transfer means responsive to said movement of said carriage for transferring stitches from said needles on said one needle bed to the adjacent upper terminal portions of said guide members.

2. In a knitting machine as set forth in claim I, the spacing of said upper terminal portions in said common direction being different from the corresponding spacing of said lower terminal portions.

3. In a knitting machine as set forth in claim 2, the spacing of said knitting needles being different from the spacing of said point members.

4. In a knitting machine as set forth in claim 1, moving means for moving said other needle bed toward and away from said one needle bed in timed sequence with said movement of the carriage.

5. In a knitting machine as set forth in claim I, said lower terminal portions and the adjacent point members constituting respective pairs members, one member of each pair being formed with a recess, the improvement further comprising moving means for moving the members of each pair relative to each other in timed sequence with said movement of the carriage toward and away from a position in which the other member of the pair is received in the recess of said one member and the members of said pair are aligned in the direction of elongation of said guide member.

6. In a knitting machine as set forth in claim 5, said upper terminal portions having respective, approximately hookshaped free ends directed toward said one needle bed, and a part of each guide member spacedly adjacent said free end being offset laterally for abutting engagement with said one needle bed when the members of each of said pairs are moved away from said position thereof.

7. In a knitting machine as set forth in claim 6, said stitch transfer means including a resilient member mounted on each of said upper portions, and cam means on said carriage engageable with said resilient members for moving the upper portions toward said needles on said one needle bed in timed sequence with said movement of the carriage. 

1. In a knitting machine having a frame, two straight needle beds mounted on said frame, said needle beds being elongated in a common, horizontally extending direction and transversely spaced so as to define a knitting space therebetween, a set of knitting needles juxtaposed in said common direction in substantially uniformly spaced relationship, each knitting needle being movable on the associated needle bed into and out of said knitting space, and operating means for moving said needles in times sequence, said operating means including a carriage mounted on said frame for reciprocating movement in said common direction, the improvement which comprises: a. an elongated transfer member carrying a set of point members in longitudinally and substantially uniformly spaced relationship; b. mounting means for releasably mounting said transfer member on said frame in a position in which said transfer member is elongated in said common direction and downwardly spaced from said needle beds; c. guide means for guiding respective stitches of a fabric knitted on one of said needle beds to said transfer member,
 1. said guide means including a set of elongated guide members dimensioned to be received in said stitches,
 2. each guide member having an upper terminal portion adjacent a respective knitting needle on said one needle bed and a lower terminal portion adjacent a respective point member on said transfer member,
 3. said guide members being spaced from each other in said common direction; and d. stitch transfer means responsive to said movement of said carriage for transferring stitches from said needles on said one needle bed to the adjacent upper terminal portions of said guide members.
 2. each guide member having an upper terminal portion adjacent a respective knitting needle on said one needle bed and a lower terminal portion adjacent a respective point member on said transfer member,
 2. In a knitting machine as set forth in claim 1, the spacing of said upper terminal portions in said common direction being different from the corresponding spacing of said lower terminal portions.
 3. In a knitting machine as set forth in claim 2, the spacing of said knitting needles being different from the spacing of said point members.
 3. said guide members being spaced from each other in said common direction; and d. stitch transfer means responsive to said movement of said carriage for transferring stitches from said needles on said one needle bed to the adjacent upper terminal portions of said guide members.
 4. In a knitting machine as set forth in claim 1, moving means for moving said other needle bed toward and away from said one needle bed in timed sequence with said movement of the carriage.
 5. In a knitting machine as set forth in claim 1, said lower terminal portions and the adjacent point members constituting respective pairs members, one member of each pair being formed with a recess, the improvement further comprising moving means for moving the members of each pair relative to each other in timed sequence with said movement of the carriage toward and away from a position in which the other member of the pair is received in the recess of said one member and the members of said pair are aligned in the direction of elongation of said guide member.
 6. In a knitting machine as set forth in claim 5, said upper terminal portions having respective, approximately hook-shaped free ends directed toward said one needle bed, and a part of each guide member spacedly adjacent said free end being offset laterally for abutting engagement with said one needle bed when the members of each of said pairs are moved away from said position thereof.
 7. In a knitting machine as set forth in claim 6, said stitch transfer means including a resilient member mounted on each of said upper portions, and cam means on said carriage engageable with said resilient members for moving the upper portions toward said needles on said one needle bed in timed sequence with said movement of the carriage. 